Suraj,
It truly depends on your lifestyle and what you feel comfortable with. Accomodation is the biggest personal expense, so with that covered, you're fortunate! For one person, groceries - bought at a modern supermarket- is $160 - $320 per month. Electricity is $60-$100 per month. Petrol for a standard-size sedan is $60 to fill the tank. If you're using rideshares (Uber, etc) budget about $60-$100 per week. Internet is $60-$100 per month, and talk-time on your phone is under $20 per month. Costs for entertainment runs the spectrum, and also depends on what you like/your lifestyle. I'd say living a typical expat life, you may be able to save up to $400 a month.
Note: There are certainly cheaper options too, like buying food at outdoor markets, not using internet often, not using air conditioning at home, or using "trotros" (public passenger vans) for transit. All options that are cheaper, but I wouldn't say convenient and sometimes not enjoyable either.